Personally I’ve got enough food stored at home to survive the initial phase but if not I’d probably rather try to raid abandoned private homes instead of heading to the closest grocery store. I believe it’s wise to avoid hotspots like that especially in the beginning.
First few weeks/months probably scavenging for supplies, canned foods, etc. like everyone else. Maybe do like that Family Guy episode and find a Twinkie factory, those things last forever LOL.